So I've been bitching and moaning since forever about the fact that KT88s couldn't be used in the JSX. Recently I learned of straight bottle 6550s that did indeed fit. Long story short, asked questions, did some research, ordered the tubes. Popped them in a couple days ago.
Thick fat bassy aggressive tone and I'm loving the hell out of it. I'm running the bias low just to be on the safe side, but I'm sending the amp off very very soon to get upgraded screen grid resistors and a couple other things to help accomodate the knew tubes.
So I'm playing around with the amp, checking for any signs that I could be ruining things, but so far nothing. I got bold and took the amp out of the box so i could remove those bear trap tube holders since they are useless. I've never taken an amp out of it's casing before, but damn it looks sexy. I'll NEVER play another amp that can't take 6550s or KT88s...it's just that damn good.
As for the difference? Extremely tight yet ultra deep low end. Not just "bass" that's boomy but a deeper punchier sound. The mids sit right where they should and they don't get out of hand even if I crank them.They've gotten fatter too. The highs I'm now backing off of because the tubes seem to have good highs as long as you keep them down. Peavey is notorious for that certain character in the treble knobs and these tubes will amplify it if you keep them high. The presence and resonance knobs I don't use much anymore. Even with the KT77s I didn't use the presence at all and I bumped the Res to just under 1, now I just leave it off.
This amp now has more low end and punch than before and it was already mean to begin with. I'm going to have to adjust my 10 band EQ a little differently now, but I like the change. These tubes definately help me push the Vader cab, as it sounds a lot fuller now and the rig sounds more like a cohesive unit.
Now a couple of clips for comparing. I tried to do a clip using a similar riff as another one of my previous clips..not exact because it wasn't written, just improvised. I did that so I can give as accurate a comparison as I can.
This clip is done with the KT77s, with 10 band eq in the loop for fattening. I don't recall if I used a boost for this or not.
Bass:7
Mids:7
Treble:6
Fat switch: on
Resonance: 0.5
Presence: off
This clip is with the 6550s. NO 10 BAND EQ USED AT ALL. No boost used
Bass:6
Mids:6.5
Treble:6
Fat Switch: On
Resonance: Off
Presence: Off
The same cab, guitar, etc were used, only thing different is the tubes. I had to back off on some of the eq with the 6550's because the amp doesn't need to be turned up that much anymore and even what I have now is rather generous. I'm also not using the 10 Band because, I just don't need it anymore...at least at the moment. It sounds a hell of a lot thicker without all that now.
Thick fat bassy aggressive tone and I'm loving the hell out of it. I'm running the bias low just to be on the safe side, but I'm sending the amp off very very soon to get upgraded screen grid resistors and a couple other things to help accomodate the knew tubes.
So I'm playing around with the amp, checking for any signs that I could be ruining things, but so far nothing. I got bold and took the amp out of the box so i could remove those bear trap tube holders since they are useless. I've never taken an amp out of it's casing before, but damn it looks sexy. I'll NEVER play another amp that can't take 6550s or KT88s...it's just that damn good.
As for the difference? Extremely tight yet ultra deep low end. Not just "bass" that's boomy but a deeper punchier sound. The mids sit right where they should and they don't get out of hand even if I crank them.They've gotten fatter too. The highs I'm now backing off of because the tubes seem to have good highs as long as you keep them down. Peavey is notorious for that certain character in the treble knobs and these tubes will amplify it if you keep them high. The presence and resonance knobs I don't use much anymore. Even with the KT77s I didn't use the presence at all and I bumped the Res to just under 1, now I just leave it off.
This amp now has more low end and punch than before and it was already mean to begin with. I'm going to have to adjust my 10 band EQ a little differently now, but I like the change. These tubes definately help me push the Vader cab, as it sounds a lot fuller now and the rig sounds more like a cohesive unit.
Now a couple of clips for comparing. I tried to do a clip using a similar riff as another one of my previous clips..not exact because it wasn't written, just improvised. I did that so I can give as accurate a comparison as I can.
This clip is done with the KT77s, with 10 band eq in the loop for fattening. I don't recall if I used a boost for this or not.
Bass:7
Mids:7
Treble:6
Fat switch: on
Resonance: 0.5
Presence: off
This clip is with the 6550s. NO 10 BAND EQ USED AT ALL. No boost used
Bass:6
Mids:6.5
Treble:6
Fat Switch: On
Resonance: Off
Presence: Off
The same cab, guitar, etc were used, only thing different is the tubes. I had to back off on some of the eq with the 6550's because the amp doesn't need to be turned up that much anymore and even what I have now is rather generous. I'm also not using the 10 Band because, I just don't need it anymore...at least at the moment. It sounds a hell of a lot thicker without all that now.
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Cool that they're working out well for you dude; 6550's = KT88's, right?
